TN 
A90 

C4D2 


BANCROFT 
LIBRARY 


THE  LIBRARY 

OF 

THE  UNIVERSITY 

OF  CALIFORNIA 


DfiPARTMENf  OF  THE  INTERIOR 

UNITED    STxVTi:S    GEOLOGICAL    SURVEV 
J.  W.  POWELL  DIRECTOR 


C  IT  Pv  O  M  I  U  M 


l^^VID    T.   IJA  Y 


ABSTRACT   FROM    "MINERAL    RESOURCES    OF    THE    UNITED    STATES, 

CALENDAR  YEARS  188:?  AND  1884"— ALBERT  WILLIAMS,  JR., 

CHIEF  OF  DIVISION  OF  MINING  STATISTICS 


WASHINGTON 

GOVERNMENT    PRINTING    OFFK^E 

1885 


ryA£^^dmt(ym 


r 


//nrM 


T 


'^  /C  yj.^~\ 


DEPARTMENT  Of  THE  INTERIOR 

UNITED    STATES    GEOLOGICAL    SURVEY 
J.  W.  POWELL   DIRECTOK 


CHROMIUM 


BY 


D^VID   T.   D^Y 


ABSTRACT   FROM    -'MINERAL    RESOURCES   OF   THE    UNITED   STATES, 

CALENDAR  YEi^S  1883  AND  1884"— ALBERT  WILLIAMS,  JR., 

CHIEF  OF  DIVISION  OF  MINING  STATISTICS 


WASHINGTON 

GOVERNMENT    PRINTING    OFFICE 

1885 


Digitized  by  the  internet  Arclnive 

in  2007  witln  funding  from 

IVIicrosoft  Corporation 


littp://www.arcliive.org/details/cliromiumOOdaydricli 


CiD 


CHROMIUM. 

By  David  T.  Day. 

History  of  the  chromium  industry. — Just  as  the  industry  of  nickel  and 
cobalt  has  been  developed  entirely  in  one  locality,  Camden,  New  Jersey, 
so  the  chromium  industry  has  found  its  development  entirely  in  the 
neighborhood  of  Baltimore,  Maryland,  and  one  firm  has  been  instru- 
mental in  bringing  it  to  its  present  condition,  although  the  industry  has 
spread  to  the  Pacific  coast,  and  the  firm  has  reached  the  fourth  genera- 
tion. About  sixty  years  ago  it  became  known  to  Mr.  Isaac  Tyson  that 
chrome  iron  ore  occurred  on  his  farm  at  Bare  Hills,  Baltimore  county, 
Maryland.  His  son,  also  named  Isaac  Tyson,  who  was  engaged  in  the 
mining  business,  began  working  out  the  ore  and  shipped  it  to  England. 
In  1833  he  entered  into  an  agreement  with  an  Englishman  of  reputed 
scientific  ability  to  begin  the  manufacture  of  paints,  for  which  the 
chrome  ore  was  decomposed  and  transformed  into  various  pigments. 
The  knowledge  of  the  Englishman  proved  inadequate,  and  the  venture 
was  not  successful.  Mr.  Tysoit,  although  actively  engaged  in  business 
pursuits,  then  began  to  study  the  various  processes  for  working  up 
chrome  ore  and  similar  substances,  supplying  the  want  of  scientific  train- 
ing by  most  assiduous  study  of  the  scattered  literature  which  France 
and  other  countries  could  furnish  relative  to  such  subjects.  Meanwhile 
chrome  ore  was  again  shipped  to  England,  this  being  the  only  demand 
for  it  until  about  1843.  The  deposits  at  Bare  Hills  never  furnished  much 
ore;  they  were  rapidly  exhausted,  and,  the  trade  with  England  being 
once  started,  inquiry  was  made  for  new  deposits.  Wherever  ore  was 
reported  it  was  at  once  investigated,  and,  if  valuable,  controlled  by  Mr. 
Tyson.  In  this  way  ore  was  discovered  and  worked  out  in  large  quan- 
tities at  Soldier's  Delight,  Baltimore  county.  In  Harford  county  an 
enormous  deposit  was  found  which  furnished  ore  steadily  for  more  than 
forty  years.  In  Cecil  county  ore  was  again  found,  and  another  large 
deposit  at  Wood's  mine,  Lancaster  county,  Pennsylvania.  When  this 
deposit  and  others  in  Delaware  and  Chester  counties  were  reached,  Mr. 
Tyson  feared  that  more  mines  might  be  discovered  than  could  be  oper- 
ated by  himself,  the  English  market  might  become  overrun  with  ore 
and  leave  no  sale  for  his  own  product  in  Maryland.  To  make  an  inde- 
pendent market,  therefore,  for  his  ore,  Mr.  Tyson  again  applied  his  study 
to  manufacturing,  and  with  such  phenomenal  success  that  the  works 
established  in  1845  for  utilizing  chrome  ore  still  monopolize  the  chromium 
industry  in  the  United  States.    At  first  the  yearly  amount  of  chromium 

567 


568  MINERAL   RESOURCES. 

salts  made  was  in«i.giiiicant,  but  gradtasilly  tiiey  replaced  the  importa- 
tion from  England,  until  finally  the  Baltimore  chrome  works  supplied 
this  country  entirely. 

The  secret  of  success  in  the  "Tyson  works"  lies  in  some  unpublished 
feature  of  their  method  of  decomposing  chrome  iron  ore.  This  substance 
resists  the  action  of  most  chemical  agents  to  an  exceptional  degree. 
Until  the  year  1820  chrome  iron  ore  was  decomposed  by  roasting  with 
potassium  nitrate  (niter).  In  that  year  Kochlin  introduced  certain 
chromium  salts  in  the  process  of  Turkey-red  dyeing,  and  they  soon  were 
employed  for  a  variety  of  purposes,  especially  in  connection  with  dyeing 
wool.  The  increased  consumption  led  to  improvements  in  the  decom- 
position of  the  ore,  and  potassium  carbonate  was  introduced  in  the 
manufacture,  instead  of  potassium  nitrate;  the  oxidation  was  effected 
by  atmospheric  oxygen  in  reverberatory  furnaces.  About  the  year  1845 
an  important  improvement  was  made  by  Stromeyer  in  the  introduction 
of  a  certain  quantity  of  lime  together  with  potassium  carbonate.  Not 
only  was  a  saving  of  alkali  effected,  but  the  oxidation  was  rendered 
easier,  inasmuch  as  the  whole  mass  did  not  fuse,  and  therefore  remained 
porous  and  more  capable  of  absorbing  the  atmospheric  oxygen,  (a)  As 
at  present  understood,  therefore,  the  decomposition  of  chrome  ore  con- 
sists in  powdering  the  mineral  by  means  of  good  millstones,  heating  it 
for  some  hours  in  a  reverberatory  furnace  with  potassiam  carbonate  and 
lime  in  certain  proportions,  and  dissolving  out  the  chromium  from  the 
fused  mass  by  water,  in  the  form  of  potassium  chromate,  which  is  con- 
verted into  bichromate  by  sulphuric  acid.  This  operation  is  put  down 
in  the  text  books  as  comparatively  simple;  but  in  the  past  twelve  years 
no  less  than  fifteen  attempts  have  been  made  to  establish  works  for  de- 
composing chrome  ore,  in  Philadelphia,  I^ew  York,  and  Boston.  It  is, 
however,  an  extremely  difficult  matter  so  to  regulate  the  manufacture 
as  to  produce  potassium  bichromate  at  the  present  market  price.  This, 
by  long  experience  and  devices  known  to  itself,  the  Baltimore  firm  is 
able  to  do. 

Domestic  sources. — Chromium  is  found  in  irregular  deposits  in  several 
widely  separated  districts  in  the  United  States.  Its  presence  is  usually 
indicated  by  the  associated  serpentine  rock.  The  two  districts  which 
have  an  important  bearing  on  the  industry  are  located  one  in  Maryland 
and  Pennsylvania  and  the  other  in  California.  Of  these  tbe  Maryland 
district  begins  in  the  Green  Spring  valley,  in  Baltimore  county,  and 
extends  through  Harford  and  Cecil  counties,  ending  in  Lancaster,  Dela- 
ware, and  Chester  counties,  Pennsylvania.  In  this  district  the  deposits 
occur  irregularly  through  the  counties  named.  Bare  Hills  and  Soldier's 
Delight,  near  Owen's  Mills,  in  Baltimore  county,- have  furnished  some- 
what more  than  5,000  tons  of  sand  ore.  Eeed's  mine,  in  Harford  county, 
furnished  over  100,000  tons.    Wood's  mine,  in  Little  Britain  township, 

a  Roscoe  and  Schorl emmer's  Treatise  on  Chemistry,  Vol,  II.,  part  2,  page  171. 


CHROMIUM.  '  569 

Lancaster  county,  Pennsylvania,  is  an  old  and  well-known  deposit, 
from  which  considerable  ore  has  been  sent  to  Baltimore.  Low's,  Line- 
pit's,  and  Jenkins's  mines  are  also  noted  deposits,  in  Fulton  township, 
Lancaster  county.  In  Chester  county  chromium  is  found  in  Elk  and 
Nottingham  townships.  It  is  also  found  in  Mid  die  town  and  Marple 
townships,  Delaware  county,  Pennsylvania. 

A.  few  isolated  occurrences  of  chromium  ores  have  been  noted,  though 
not  mined,  in  States  north  of  the  Maryland  district:  in  ISTew  York,  at 
Phillipstown,  Putnam  county,  and  at  Wilke's  mine,  Monroe,  Orange 
county;  in  Massachusetts,  in  Blandford  and  Chester  townships,  Hamp- 
den county;  in  Vermont,  in  Jay,  Troy,  and  Westfield  townships,  Orleans 
county. 

South  of  the  Maryland  district  chromium  is  found  in  Virginia,  at 
Drainesville,  near  the  Potomac,  in  Fairfax  county.  Quite  recently  a 
deposit  of  chrome  ore  was  reported  in  Jackson  county.  North  Carolina, 
which,  as  stated  in  the  last  report,  i3romised  to  yield  ore  of  better  qual- 
ity than  any  other  in  the  eastern  States.  The  deposit  has  not,  how- 
ever, been  worked  up  to  the  i)resent.  Chrome  ore  is  known  to  occur  in 
small  quantity  in  North  Carolina,  in  Guilford  county;  at  Cullasaja, 
Higdon's,  Elijay's  creek,  and  Moore's  mine,  Macon  county,  and  in  Yan- 
cey, Clay,  Mitchell,  Burke,  and  Watauga  counties. 

Until  about  three  years  ago,  the  Maryland  district  included  in  it 
nearly  all  the  mines  from  which  chromium  was  obtained,  but  since  then 
an  entire  change  has  been  made  in  the  supply.  The  eastern  mines 
have  been  practically  abandoned,  and  now  all  the  ore  comes  from  the 
more  recently  discovered  deposits  in  CalifDrnia.  Fifteen  years  ago 
Messrs.  Tyson  &  Sons  were  informed  by  their  attorney  in  West  Ches- 
ter, Pennsylvania,  that  his  brother,  living  in  Del  Norte  county  in  the 
extreme  northwestern  part  of  California,  had  discovered  chrome  ore  on 
his  farm.  About  this  time  Mr.  Simpson,  a  Baltimore  merchant,  urged 
the  Tysons  to  aid  him  in  working  gold  mines  of  reported  immense  value 
in  Arizona.  A  surveyor  Vas  sent  by  the  Tysons  to  Arizona  with  Mr. 
Simpson  to  in  vestigate  the  supj^osed  gold  deposits.  They  proved  worth- 
less, and  after  JNIr.  Simpson  had  been  killed  by  hostile  Indians,  the  sur- 
veyor thought  it  best  to  investigate  another  region  and  examine  the 
reported  chromium  deposits  in  California.  They  proved  to  be  horn- 
blende rock  without  v;ilue,  but  by  a  mere  accident,  which  has  always 
been  a  feature  of  chromium  discoveries,  he  found  a  large  deposit  of 
chrome  iron  ore  in  another  part  of  the  county.  For  some  years  past 
the  deposit  has  been  worked  and  large  quantities  of  ore  have  been  ex- 
tracted by  the  Tyson  Mining  Company,  and  as  yet  there  are  no  signs 
of  exhaustion  in  this  field.  Following  the  discovery  in  Del  Norte  county 
came  that  of  ore  in  Sonoma,  San  Luis  Obispo,  and  Placer  counties;  and 
chromium  is  now  known  to  be  common  throughout  California,  having 
been  noticed  in  more  than  half  the  counties  of  the  State.    The  unde- 


570  MINERAL    RESOURCES. 

veloped  fleposits  aud  mere  croppings  are,  in  fact,  too  many  to  admit  of 
their  enumeration  here.  Chromium  also  occurs  elsewhere  on  the  Pa- 
cific coast,  but  to  what  extent  or  of  what  quality  has  not  been  deter- 
mined, no  attempts  at  utilizing  it  having  been  made  except  in  Califor- 
nia, where  it  has  been  mined  and  shipped  to  eastern  markets  at  the 
rate  of  about  3,000  tons  per  year  since  its  discovery.  The  deposits  in 
California  most  entitled  to  notice,  because  of  their  magnitude,  good 
grade,  or  the  extent  to  which  they  have  been  worked,  are  the  follow- 
ing :  Kear  Litton  Springs,  Sonoma  county,  from  which  there  were  ex- 
tracted some  years  ago  about  2,000  tons  of  ore,  cost  of  mining  and  de- 
livering at  San  Francisco  about  $4.50  per  ton,  average  price  obtained 
about  $9  per  ton  5  Sow  Divide  copper  mines,  Del  Norte  county,  from 
which  there  were  taken  some  years  ago  several  thousand  tons  of  good 
chrome  ore — no  work  has  been  done  there  lately;  Campo  Seco,  Cala- 
veras county,  a  good  article  and  in  large  quantity.  This  last-named 
deposit  can  be  worked  to  good  advantage  when  the  narrow-gauge  rail- 
road now  in  course  of  construction  shall  reach  Campo  Seco.  In  San 
Diego  gulch,  in  the  same  county,  there  is  said  to  be  an  isolated  mass 
of  chrome  iron  that  Avill  weigh  thousands  of  tons.  From  the  chrome 
mines  of  San  Luis  Obispo  county  the  largest  amount  of  ore  has  been 
shipped,  the  total  exceeding  15,000  tons.  This  was  a  number  of  years 
ago,  no  shipments  having  been  made  lately  from  that  county  owing 
to  the  low  prices  of  chrome  ore.  Most  of  the  chrome  now  being  ex- 
tracted in  California  comes  from  Placer  county,  from  which  shipments 
have  averaged  in  1883  aud  1884  about  2,000  tons  per  annum.  Just  now 
this  industry  is  much  depressed  in  California,  but  with  prices  slightly 
improved  it  would  more  than  regain  its  former  activity.  All  of  the 
sources  utilized  are  as  a  rule  worked  by  the  Tyson  Mining  Company. 
Other  companies  are  also  engaged  in  the  workof  extractiug  ore  in  a  small 
way.  It  is  taken  by  wagons  to  the  nearest  railroad  and  transported  to 
San  Francisco.  If  not  already  the  property  of  the  Tysons  it  is  all 
bought  by  them  and  shipped  in  sailing  vessels  by  way  of  Cape  Horn  to  ; 
Baltimore.     A  small  amount  is  exported. 

At  present  there  is  no  indication  of  exhaustion  in  the  California 
mines,  and  yet  every  effort  is  being  made  to  discover  new  deposits,  for  : 
the  reason  that  these  deposits  are  not  found  in  veins  or  leads  from  the 
direction  of  which  new  mines  can  be  predicted,  but  in  isolated  pockets 
of  all  sizes,  sometimes  yielding  only  a  few  pounds  and  sometimes  many 
thousand  tons.  The  miner  is  never  sure  but  that  the  next  day  may  find 
his  deposit  exhausted  or  the  quality  of  the  ore  no  longer  profitable. 
The  only  rule  that  has  been  found  is  that  the  ore  is  richest  at  the  sur- 
face and  decreases  in  value  as  the  mine  become  deeper.  The  value  of 
a  mine  decreases  very  rapidly  with  the  depth ;  for,  in  addition  to  the 
cost  of  getting  ore  to  the  surface  and  of  keeping  out  water  from  the^j 
mine,  the  ore  contains  less  chromium.    The  mines  in  the  eastern  States  « 


m 


CHROMIUM. 


571 


are  by  no  means  exhausted  j  the  reason  why  the  Califbrnia  ores  have 
been  substituted  is  because  they  are  nearer  the  surface  and  therefore 
richer.  As  the  cost  of  grinding  and  decomposing  the  ore  is  the  same 
for  rich  as  for  poor  grades  the  rich  ores  are  more  profitable  ;  moreover 
the  higher  the  percentage  of  chromium  in  the  ore  the  easier  is  its  de- 
composition. 

The  general  results  of  over  one  hundred  analyses  of  ore  found  in  Cali- 
fornia may  be  given  as  follows : 


Del  Norte  county  ...... 

Napa  county 

Placer  county 

Tuolumne  county 

San  Luis  Obispo  county 
El  Dorado  county ...... 


Chromic 
oxide. 


Per  cent. 
39  to  45 
42  to  46 
35  to  55 
44  to  45 
38  to  60 
20 


Foreign  sources. — Ores  of  the  same  character  as  those  of  California 
are  found  in  Turkey,  Russia,  and  Asia  Minor.  From  this  last  source  a 
small  quantity  of  ore  annually  finds  its  way  to  Baltimore.  The  amount, 
however,  is  small  and  irregular.  Nearly  all  the  ore  which  supplies  the 
Scotch  and  French  manufactories  of  chromium  salts  comes  from  Eussia. 
The  ore  is  mined  in  Siberia  and  transported  to  St.  Petersburg  on  rafts 
down  the  various  watercourses.  These  rafts  start  on  their  journey  in 
the  spring,  are  frozen  up  all  of  the  next  winter,  and  reach  their  desti- 
nation the  second  summer.  The  rafts  are  sold  for  lumber  and  the  ore 
is  shipped  to  England.  By  this  means  ore  is  mined  in  a  remote  region 
at  small  expense;  without  this  cheap  system  of  rafting  competition 
with  American  ores  would  be  impossible. 

Character  of  the  ores, — Chromium  occurs  as  a  constituent  of  sev- 
eral minerals.  Cr^coite,  for  example,  is  chromate  of  lead ;  the  green 
color  of  the  emerald  is  due  to  traces  of  chromium ;  while  i)enninite, 
chromic  mica  or  fuchsite,  and  other  minerals  owe  their  color  to  this 
metal.  But  the  ore  from  which  chromium  is  always  obtained  is  chro- 
mite  or  "  chrome  ironstone."  Its  composition  may  be  expressed  by  the 
formula  FeCr204 ;  but  part  of  the  chromium  may  be  replaced  by  iron, 
or  the  iron  may  be  partly  replaced  by  magnesium,  and  the  replacements 
are  found  in  ore  far  removed  from  the  surface  of  the  ground.  Alumi- 
num is  also  sometimes  present,  and  silica  is  often  found  in  the  sand 
ore,  or  ore  containing  the  chromite  in  the  form  of  small  grains.  The 
purest  ore  is  found  in  lumps  weighing  sometimes  several  pounds. 


572 


MINERAL    RESOURCES. 


FroducUon. — The  following  table  represents  about  the  amount  of  ore 
mined  in  the  last  three  years  j  it  is  all  from  California : 

Production  of  chrome  ore  in  California. 


Years. 

Tons 
of  2,240 
pounds. 

Value 
inCaU- 
fomia. 

1882 

2,500 
3,000 
2,000 

$50,  000 
60,  000 
35,  000 

1883 

1884 

7,500 

145,  000 

There  is  no  regular  spot  value  for  chrome  ore  at  the  mines,  as  the 
cost  varies  irregularly  in  each  district  and  much  is  mined  by  the  manu- 
facturers' agent  who  owns  the  mine.  In  San  Francisco  tlie  ore  is  worth 
from  $18  to  $20  per  long  ton.  By  the  time  it  reaches  Baltimore  the 
cost  is  from  $35  to  $40  per  long  ton.  The  total  amount  expended  there- 
fore for  chrome  ore  in  1883  and  1884  was  about  $190,000. 

Exports. — The  value  of  ore  exported  from  1864  to  1883  is  given  in  the 
following  table : . 

Value  of  chrome  ores  exported  from  the  United  States,  1864  to  1883  inclusive. 


Fiscal  years  ending  June  30— 

Value. 

1864  

$39,  585 
19,  078 
2,080 
4,2«8 
7,540 
1,548 
2,905 
(a) 

1865 

1873          

1874 

1880  ... 

1 882 

1883 

1884 

a  ^Tone  reported. 

Utilization. — Nearly  all  of  the  chrome  ore  used  in  the  United  States 
is  made  into  potassium  bichromate  by  Jesse  Tyson  &  Sons,  at  Baltimore. 
About  50  tons  a  year  is  made  into  chrome  steel  at  the  Brooklyn  Chrome 
Steel  Works.  Potassium  bichromate  is  therefore  the  one  salt  from 
which  all  other  compounds  have  been  obtained.  The  amount  of  potas- 
sium bichromate  produced  in  the  United  States  is  in  all  about  1,500  tons 
a  year.  Of  this,  a  small  quantity,  amounting  to  about  250  tons  a  year, 
is  made  by  Harrison  Bros.,  who  have  been  making  bichromate  for  about 
three  years  past  at  the  branch  of  their  color  works  called  the  Kalion 
Works,  Philadelphia. 

Imports. — Besides  the  domestic  product  about  1,000  tons  of  bichro- 
mate are  annually  imported  from  Scotland  under  a  duty  of  3J  cents  per 
pound.  Chromic  acid,  which  is  obtained  from  the  bichromate,  is  also 
imported  in  small  amounts ;  it  would  probably  become  a  more  extensive 
article  of  commerce  except  for  the  danger  of  its  setting  fire  to  vessels 
and  storehouses.  The  following  table  gives  the  actual  amounts  im- 
ported and  their  value  from  1867  to  the  end  of  the  fiscal  year  1884: 


573 


Chromate  and  hichromate  of  potash  and  chromic  acid  imported  and  entered  for  consumption 
in  the       -    -  -  —         - 


CHROMIUM. 

id  chromic  acid 
in  the  United  States,  1867  to  1884  inclusive. 


Fiscal  years  ending  Jane  80 — 

Chromate  and  bichro- 
mate of  potash. 

Chromic  acid. 

Total 
value. 

Quantity. 

Value. 

Quantity. 

Value. 

1867 

Founds. 

875, 205 

777,  855 

877,  432 

1, 235,  946 

2, 170, 473 

1, 174,  274 

1,121,357 

1,  387,  051 

1,  417,  812 

1,  665,  Oil 

2,471.669 

1,  929,  670 

2,  624, 403 

3,  505,  740 
4, 404,  237 
2,  449,  875 
1,990,140 
2,  593, 115 

$88,787 
68,  634 
78,  288 
127,  333 
223,  529 
220,  HI 
178,  472 
218,  517 
183,424 
175,  795 
264,  392 
211, 136 
221, 151 
350,279 
402,  088 
261,  006 
208,  681 
210,  677 

Founds. 

$88.  787 

1868 

68, 634 

1869    

1 

276 

11 

45 
10 
35 

78, 2»l 

1870 

127, 341 

1871                                                       

223, 534 

1872 

514 
922 
44 
45 
120 
13 
32 

220, 160 

1873 ^ 

1874 

178,  748 
218,530 

1875 

183,  446 

1876    

175,  840 

1877 

264,  402 

1878    

211,171 

1879 

221, 151 

1880                                            

5 
124 

52 
290 

3 

89 

42 

338 

•120 

350, 281! 

1881 

402, 177 

1882 

261,048 

1^83 

209,  019 

1884 

210,  797 

Sodium  Mchr ornate. — On  account  of  the  less  cost  of  sodium  carbonate 
it  has  frequently  been  proposed  to  substitute  it  for  potassium  carbonate 
in  the  deopmposition  of  chrome  iron  ore,  and  thus  produce  sodium  bi- 
chromate instead  of  the  potassium  compound.  There  are  several  obsta- 
cles to  this:  The  decomposition  is  not  as  readily  affected  with  sodium 
carbonate  as  with  potash,  and,  further,  sodium  bichromate  is  by  no 
means  as  easy  to  crystallize  as  the  potassium  salt,  and  in  fact  it  is  with 
great  difficulty  that  sodium  bichromate  can  be  crystallized  at  all.  But 
about  three  years  ago  the  manufacture  of  sodium  bichromate  was  intro- 
duced by  German  chemists,  and  the  effect  on  the  industry  can  already 
be  seen.  Before  this  *  German  innovation,  factories  in  Scotland  and 
France  supplied  Europe  with  chromium  salts.  The  introduction  of  so- 
dium bichromate  has  brought  about  competition  with  Germany,  amount- 
ing to  a  chromium  war.  The  Scotch  and  German  manufacturers  are 
trying  each  to  drive  the  other  from  the  field.  In  1882  the  price  of  po- 
tassium bichromate  was  15J  cents  per  pound.  In  1883  it  fell  to  12  cents, 
and  it  now  is  selling  in  this  country  at  lOJ  cents,  the  lowest  price  it  has 
ever  reached.  What  the  outcome  of  this  competition  may  be  can  be 
surmised  from  the  fact  that  within  the  last  few  months  the  Baltimore 
firm  has  begun  the  manufacture  of  sodium  bichromate,  though  only  as 
an  experiment  so  far.  For  many  purposes  sodium  bichromate  can  take 
the  place  of  the  potassium  salt  without  disadvantage.  For  example,  in 
any  use  where  the  oxidizing  action  of  the  salt  is  the  only  point  to  be 
considered,  as  in  the  manufacture  of  Turkey  red,  or  alizarine,  one  salt  is 
as  useful  as  the  other.  The  most  important  application  of  potassium 
bichromate  in  the  arts  is  for  calico  printing.  For  this  purpose  dyers 
l^refer  potassium  bichromate  to  sodium  bichromato.  In  how  far  this  is 
mere  prejudice  it  is  not  possible  to  say.  In  the  manufacture  of  pigments, 
in  which  bichromates  find  application  for  making  '^  chrome  yellow,'^ 
^'chrome  orange,'^  and  ^^ chrome  green^"  either  salt  can  be  used. 


